Process of making radiocabinets



May 25 1926.

G. W. BULLEY PROCESS oF MAKING RADIOCABINETS Filed. July 30, 1925 Patented May 25, `192e.

UNITED STATES PATENT OFFICE.

GEORGE W. BULLEY, or ARRON, OHIO, -AssIGNoR To T IIE MILLER RUBBER COMPANY,

or* AKRON, OHIO. A CORPORATION OP oIIIo.

PROCESS or MARINGRADIOOABINRTS.

Application led July 30, 1925. Serial No. 47,11'8.

Figure 1 shows a blank from which the I body of the article is made.

A Fig. 2 is a transverse sectional view of edges of the a mold showing the blank with receptacle shape and the top blank applied. l

Fig. 3 is a sectional detail showing the preferred manor 'of forming the' grid openv1n s.

ig. 4 is a front elevation of article, and vz Fig. 5 is a sectional detail on line 5-5 of Fig. 4. .t

Referring vby reference characters to this drawing the numeral 1 designates a blank or sheet of hard rubber compound such as I refer rto use comprising a rectangular portion 1 of the size and shape required for the bottom of the articleand four (preferably integral) flaps 1`a for forming the four side walls, which blank may be conveniently cut from a single sheet of the proper size. The four flaps are then turned up or folded to bring their edges into abutting posithe completed tions, such' edges bein pressed together and caused to adhere by t e tacky nature of the unvulcanized material If desired the folding and pressing may be facilitated byl the use of a suitable mandrel or| form which, would be removed afterthe shaping action. Such open topped receptacle like article is then placed in a mold 2 having the desired interior configurations, a suitable gas fortning material or blower 3 deposited therein, and a"y top forming blank l" is applied, its edges being ody portion, preferably so as to make an out turned seam as indicated at 1. Thereafter the nold is closed and subjected to the vulcanizing temperature.

The inold is provided with an enlarged bottom portion or mold cavity 2El to give tol the completed article a broader base, and is also provided withan enlarged uppei portion 2b separated from the-lower portion by a shoulder 2, and-the upper portion may pressed into contact with the.

also be provided with a groove or channel around the top. y

After the mold is closed and heated the 4a-siication of the blower produces internal uid pressure which expands -the rubber 56 2d to form an ornamental head or flange compound and causes it to. take the exact v shape of the mold cavity. v

The side walls of the enlarged upper portion are offset sufficiently from the .lower wall portions to cause the upper part of the container to be as much larger than the lower, (in cross sectional area) as the thickness of the walls, or slightly greater. Then by making saw cuts on the lines a and b and discarding the intervening material the top portion w-ill form a slip or telescoping cover and will fit in position as shown in Fig. 4.

When articles of this nat e are seamed together at the corners a lridge ldis likely to occur at the corners which would interfere withthe telescoping of the cover. To avoid the effects of this I provide the mold at the upper corners at the proper place with ribs or enlargements which cause an inward 'bulge 1e of the body portion at the corners Where the cabinet is to be used for loud speaker purposes it is desired to form the front as a grid. yA convenient manner of effecting this is to provide the front mold Wall with ribs 2t in its inner face ofthe proper shape, around which the rubber is forced by the blower in the shape of folds 1f. Then by grinding off these ridges the material is severed on the lines of the folds and the severedmaterial removed, leaving grid openings.

What I claim is:

1. The hereindescribed method of-making hard' rubber containers having slip covers which consists in producing by vulcanization a unitary closed article having atop portion Iv of larger sectional area and a remaining portion 'having rebated corners and severing said enlarged portion.

2. The hereindescribed method of making a hard Arubber container havingopenings in the walls thereof which consists -1n producing by vulcanization 'a hard rubber container body having projecting or bulged portions defining said openings and removing said bulged portions.

3. The hereindescribed method of making a hard rubber container having openings in the walls thereof which consists in producing by vulcanization a hard rubber container body having projecting ribs defining said olenings, and thereafter grinding o said r1 s.

4. The hereindes'cribed method of making a container of hard rubber having a slip cover, which consists in forming a hollow body of hard rubber compound, enclosing the same in a mold having an enlarged upper part and designed so as to be provided with convex llets in the corners belovsT said enlarged upper part, subjecting the same to curing heat with internal Huid pressure, and nally severing the top on the line of outward bulge produced by said enlarged top. 20

In testimony whereof I aliix my signature.

GEORGE W. BULLEY. 

